1. Field of the Invention
The present invention relates to a liquid quantity detecting device for detecting the quantity of liquid stored in a predetermined tank.
2. Description of the Prior Art
Previously, as a conventional liquid quantity detecting device, a device having a float which floats on the liquid has usually been used. In this device, the quantity of liquid is detected on the basis of the change of resistance between one end of a resistor and a movable contact sliding thereon. The contact is fixed to the float and moves on the resistor in accordance with the movement of the float. However, in this device, the quantity of liquid is detected on the basis of the liquid level, and, therefore, the quantity of liquid cannot be detected precisely because of the difference between the form of the tank in which the liquid is stored and the form of the surface of the resistor, and because of the difference of the resistance value due to the contact area between the contact and the surface of the resistor. Particularly when the liquid decreases to a small quantity the measurement error is large. Therefore, the present invention is proposed in order to improve the above-mentioned inaccuracy in measurement.